Sweet corn hybrid SVSK6143 and parents thereof

ABSTRACT

The invention provides seed and plants of corn hybrid SVSK6143 and the parent lines thereof. The invention thus relates to the plants, seeds, and tissue cultures of corn hybrid SVSK6143 and the parent lines thereof, and to methods for producing a corn plant produced by crossing such plants with themselves or with another corn plant, such as a plant of another genotype. The invention further relates to seeds and plants produced by such crossing. The invention further relates to parts of such plants, including the fruit and gametes of such plants.

FIELD OF THE INVENTION

The present invention relates to the field of plant breeding and, morespecifically, to the development of corn hybrid SVSK6143 and inbred cornlines SHY-6S15-9078LP and SHY-6RHBE322.

BACKGROUND OF THE INVENTION

The goal of vegetable breeding is to combine various desirable traits ina single variety/hybrid. Such desirable traits may include any traitdeemed beneficial by a grower and/or consumer, including greater yield,resistance to disease, tolerance to environmental stress, andnutritional value.

Breeding techniques take advantage of a plant's method of pollination.There are two general methods of pollination: a plant self-pollinates ifpollen from one flower is transferred to the same or another flower ofthe same plant or plant variety. A plant cross-pollinates if pollencomes to it from a flower of a different plant variety.

Plants that have been self-pollinated and selected for type over manygenerations become homozygous at almost all gene loci and produce auniform population of true breeding progeny, a homozygous plant. A crossbetween two such homozygous plants of different genotypes produces auniform population of hybrid plants that are heterozygous for many geneloci. Conversely, a cross of two plants each heterozygous at a number ofloci produces a population of hybrid plants that differ genetically andare not uniform. The resulting non-uniformity makes performanceunpredictable.

The development of uniform varieties requires the development ofhomozygous inbred plants, the crossing of these inbred plants, and theevaluation of the crosses. Pedigree breeding and recurrent selection areexamples of breeding methods that have been used to develop inbredplants from breeding populations. Those breeding methods combine thegenetic backgrounds from two or more plants or various other broad-basedsources into breeding pools from which new lines and hybrids derivedtherefrom are developed by selfing and selection of desired phenotypes.The new lines and hybrids are evaluated to determine which of those havecommercial potential.

SUMMARY OF THE INVENTION

In one aspect, the present invention provides a corn plant of the hybriddesignated SVSK6143, corn line SHY-6S15-9078LP, or corn lineSHY-6RHBE322. Also provided are corn plants having all the physiologicaland morphological characteristics of such a plant. Parts of these cornplants are also provided, for example, including pollen, an ovule,scion, a rootstock, a fruit, and a cell of the plant.

In another aspect of the invention, a plant of corn hybrid SVSK6143and/or corn lines SHY-6S15-9078LP and SHY-6RHBE322 comprising an addedheritable trait is provided. The heritable trait may comprise a geneticlocus that is, for example, a dominant or recessive allele. In oneembodiment of the invention, a plant of corn hybrid SVSK6143 and/or cornlines SHY-6S15-9078LP and SHY-6RHBE322 is defined as comprising a singlelocus conversion. In specific embodiments of the invention, an addedgenetic locus confers one or more traits such as, for example, herbicidetolerance, insect resistance, disease resistance, and modifiedcarbohydrate metabolism. In further embodiments, the trait may beconferred by a naturally occurring gene introduced into the genome of aline by backcrossing, a natural or induced mutation, or a transgeneintroduced through genetic transformation techniques into the plant or aprogenitor of any previous generation thereof. When introduced throughtransformation, a genetic locus may comprise one or more genesintegrated at a single chromosomal location.

The invention also concerns the seed of corn hybrid SVSK6143 and/or cornlines SHY-6S15-9078LP and SHY-6RHBE322. The corn seed of the inventionmay be provided as an essentially homogeneous population of corn seed ofcorn hybrid SVSK6143 and/or corn lines SHY-6S15-9078LP and SHY-6RHBE322.Essentially homogeneous populations of seed are generally free fromsubstantial numbers of other seed. Therefore, seed of hybrid SVSK6143and/or corn lines SHY-6S15-9078LP and SHY-6RHBE322 may be defined asforming at least about 97% of the total seed, including at least about98%, 99% or more of the seed. The seed population may be separatelygrown to provide an essentially homogeneous population of corn plantsdesignated SVSK6143 and/or corn lines SHY-6S15-9078LP and SHY-6RHBE322.

In yet another aspect of the invention, a tissue culture of regenerablecells of a corn plant of hybrid SVSK6143 and/or corn linesSHY-6S15-9078LP and SHY-6RHBE322 is provided. The tissue culture willpreferably be capable of regenerating corn plants capable of expressingall of the physiological and morphological characteristics of thestarting plant and of regenerating plants having substantially the samegenotype as the starting plant. Examples of some of the physiologicaland morphological characteristics of the hybrid SVSK6143 and/or cornlines SHY-6S15-9078LP and SHY-6RHBE322 include those traits set forth inthe tables herein. The regenerable cells in such tissue cultures may bederived, for example, from embryos, meristems, cotyledons, pollen,leaves, anthers, roots, root tips, pistils, flowers, seeds, stalks,silks, tassels, kernels, ears, cobs, and husks. Still further, thepresent invention provides corn plants regenerated from a tissue cultureof the invention, the plants having all the physiological andmorphological characteristics of hybrid SVSK6143 and/or corn linesSHY-6515-9078LP and SHY-6RHBE322.

In still yet another aspect of the invention, processes are provided forproducing corn seeds, plants, and fruit, which processes generallycomprise crossing a first parent corn plant with a second parent cornplant, wherein at least one of the first or second parent corn plants isa plant of corn line SHY-6S15-9078LP or corn line SHY-6RHBE322. Theseprocesses may be further exemplified as processes for preparing hybridcorn seed or plants, wherein a first corn plant is crossed with a secondcorn plant of a different, distinct genotype to provide a hybrid thathas, as one of its parents, a plant of corn line SHY-6S15-9078LP or cornline SHY-6RHBE322. In these processes, crossing will result in theproduction of seed. The seed production occurs regardless of whether theseed is collected or not.

In one embodiment of the invention, the first step in “crossing”comprises planting seeds of a first and second parent corn plant, oftenin proximity so that pollination will occur for example, mediated byinsect vectors. Alternatively, pollen can be transferred manually. Wherethe plant is self-pollinated, pollination may occur without the need fordirect human intervention other than plant cultivation. For hybridcrosses, it may be beneficial to detassel or otherwise emasculate theparent used as a female.

A second step may comprise cultivating or growing the seeds of first andsecond parent corn plants into mature plants. A third step may comprisepreventing self-pollination of the plants, such as by detasseling orother means.

A fourth step for a hybrid cross may comprise cross-pollination betweenthe first and second parent corn plants. Yet another step comprisesharvesting the seeds from at least one of the parent corn plants. Theharvested seed can be grown to produce a corn plant or hybrid cornplant.

The present invention also provides the corn seeds and plants producedby a process that comprises crossing a first parent corn plant with asecond parent corn plant, wherein at least one of the first or secondparent corn plants is a plant of corn hybrid SVSK6143 and/or corn linesSHY-6S15-9078LP and SHY-6RHBE322. In one embodiment of the invention,corn seed and plants produced by the process are first generation (F₁)hybrid corn seed and plants produced by crossing a plant in accordancewith the invention with another, distinct plant. The present inventionfurther contemplates plant parts of such an F₁ hybrid corn plant andmethods of use thereof. Therefore, certain exemplary embodiments of theinvention provide an F₁ hybrid corn plant and seed thereof.

In still yet another aspect, the present invention provides a method ofproducing a plant derived from hybrid SVSK6143 and/or corn linesSHY-6S15-9078LP and SHY-6RHBE322, the method comprising the steps of:(a) preparing a progeny plant derived from hybrid SVSK6143 and/or cornlines SHY-6S15-9078LP and SHY-6RHBE322, wherein said preparing comprisescrossing a plant of the hybrid SVSK6143 and/or corn linesSHY-6S15-9078LP and SHY-6RHBE322 with a second plant; and (b) crossingthe progeny plant with itself or a second plant to produce a seed of aprogeny plant of a subsequent generation. In further embodiments, themethod may additionally comprise: (c) growing a progeny plant of asubsequent generation from said seed of a progeny plant of a subsequentgeneration and crossing the progeny plant of a subsequent generationwith itself or a second plant; and repeating the steps for an additional3-10 generations to produce a plant derived from hybrid SVSK6143 and/orcorn lines SHY-6S15-9078LP and SHY-6RHBE322. The plant derived fromhybrid SVSK6143 and/or corn lines SHY-6S15-9078LP and SHY-6RHBE322 maybe an inbred line, and the aforementioned repeated crossing steps may bedefined as comprising sufficient inbreeding to produce the inbred line.In the method, it may be desirable to select particular plants resultingfrom step (c) for continued crossing according to steps (b) and (c). Byselecting plants having one or more desirable traits, a plant derivedfrom hybrid SVSK6143 and/or corn lines SHY-6S15-9078LP and SHY-6RHBE322is obtained which possesses some of the desirable traits of theline/hybrid as well as potentially other selected traits.

In certain embodiments, the present invention provides a method ofproducing food or feed comprising: (a) obtaining a plant of corn hybridSVSK6143 and/or corn lines SHY-6S15-9078LP and SHY-6RHBE322, wherein theplant has been cultivated to maturity, and (b) collecting at least onecorn from the plant.

In still yet another aspect of the invention, the genetic complement ofcorn hybrid SVSK6143 and/or corn lines SHY-6S15-9078LP and SHY-6RHBE322is provided. The phrase “genetic complement” is used to refer to theaggregate of nucleotide sequences, the expression of which sequencesdefines the phenotype of, in the present case, a corn plant, or a cellor tissue of that plant. A genetic complement thus represents thegenetic makeup of a cell, tissue, or plant, and a hybrid geneticcomplement represents the genetic make-up of a hybrid cell, tissue, orplant. The invention thus provides corn plant cells that have a geneticcomplement in accordance with the corn plant cells disclosed herein andseeds and plants containing such cells.

Plant genetic complements may be assessed by genetic marker profiles andby the expression of phenotypic traits that are characteristic of theexpression of the genetic complement, e.g., isozyme typing profiles. Itis understood that hybrid SVSK6143 and/or corn lines SHY-6S15-9078LP andSHY-6RHBE322 could be identified by any of the many well-knowntechniques such as, for example, Simple Sequence Length Polymorphisms(SSLPs) (Williams et al., Nucleic Acids Res., 1 8:6531-6535, 1990),Randomly Amplified Polymorphic DNAs (RAPDs), DNA AmplificationFingerprinting (DAF), Sequence Characterized Amplified Regions (SCARs),Arbitrary Primed Polymerase Chain Reaction (AP-PCR), Amplified FragmentLength Polymorphisms (AFLPs) (EP 534 858, specifically incorporatedherein by reference in its entirety), and Single NucleotidePolymorphisms (SNPs) (Wang et al., Science, 280:1077-1082, 1998).

In still yet another aspect, the present invention provides hybridgenetic complements, as represented by corn plant cells, tissues,plants, and seeds, formed by the combination of a haploid geneticcomplement of a corn plant of the invention with a haploid geneticcomplement of a second corn plant, preferably, another, distinct cornplant. In another aspect, the present invention provides a corn plantregenerated from a tissue culture that comprises a hybrid geneticcomplement of this invention.

Any embodiment discussed herein with respect to one aspect of theinvention applies to other aspects of the invention as well, unlessspecifically noted.

The term “about” is used to indicate that a value includes the standarddeviation of the mean for the device or method being employed todetermine the value. The use of the term “or” in the claims is used tomean “and/or” unless explicitly indicated to refer to alternatives onlyor the alternatives are mutually exclusive. When used in conjunctionwith the word “comprising” or other open language in the claims, thewords “a” and “an” denote “one or more,” unless specifically notedotherwise. The terms “comprise,” “have” and “include” are open-endedlinking verbs. Any forms or tenses of one or more of these verbs, suchas “comprises,” “comprising,” “has,” “having,” “includes” and“including,” are also open-ended. For example, any method that“comprises,” “has” or “includes” one or more steps is not limited topossessing only those one or more steps and also covers other unlistedsteps. Similarly, any plant that “comprises,” “has” or “includes” one ormore traits is not limited to possessing only those one or more traitsand covers other unlisted traits.

Other objects, features, and advantages of the present invention willbecome apparent from the following detailed description. It should beunderstood, however, that the detailed description and any specificexamples provided, while indicating specific embodiments of theinvention, are given by way of illustration only, since various changesand modifications within the spirit and scope of the invention willbecome apparent to those skilled in the art from this detaileddescription.

DETAILED DESCRIPTION OF THE INVENTION

The invention provides methods and compositions relating to plants,seeds, and derivatives of corn hybrid SVSK6143, corn lineSHY-6515-9078LP, and corn line SHY-6RHBE322.

Corn hybrid SVSK6143, also known as 15-6S-SHY-6143, is a yellow sh2variety intended for the processing market that comprises the RpG5 geneconferring resistance to common rust.

Corn line SHY-6S15-9078LP is a yellow sh2 inbred variety that comprisesthe Ht1 gene conferring resistance to select races of Northern corn leafblight.

Corn line SHY-6RHBE322 is an inbred variety that comprises the RpG5 geneconferring resistance to common rust.

A. Origin and Breeding History of Corn Hybrid SVSK6143

The parents of hybrid SVSK6143 are SHY-6515-9078LP and SHY-6RHBE322. Theparent lines are uniform and stable, as is a hybrid produced therefrom.A small percentage of variants can occur within commercially acceptablelimits for almost any characteristic during the course of repeatedmultiplication. However no variants are expected.

B. Physiological and Morphological Characteristics of Corn HybridSVSK6143, Corn Line SHY-6S15-9078LP, and Corn Line SHY-6RHBE322

In accordance with one aspect of the present invention, there isprovided a plant having the physiological and morphologicalcharacteristics of corn hybrid SVSK6143 and the parent lines thereof. Adescription of the physiological and morphological characteristics ofsuch plants is presented in Tables 1-3.

TABLE 1 Physiological and Morphological Characteristics of Corn HybridSVSK6143 CHARACTERISTIC SVSK6143 BASIN R 1. Type sweet sweet 2. Maturityin the Region of Best Adaptability emergence to 50% of plants in 57 days54 days silk 2191.7 heat units 2070.2 heat units emergence to 50% ofplants in 56 days 52 days pollen 2153.5 heat units 1989.6 heat units 10%to 90% pollen shed 4 days 4 days 200.5 heat units 189.9 heat units 50%silk to optimum edible 27 days 27 days quality 1122.4 heat units 1375.1heat units 3. Plant length (tassel included) medium medium plant height(to tassel tip) (cm) avg: 163.06 avg: 176.86 std dev: 26.9191 std dev:13.6008 sample size: 15 sample size: 15 ear height (to base of top earavg: 55.53 avg: 51.06 node) (cm) std dev: 6.7493 std dev: 7.6855 samplesize: 15 sample size: 15 length of top ear internode avg: 14.5 avg:14.63 (cm) std dev: 1.0351 std dev: 0.7898 sample size: 15 sample size:15 average number of tillers avg: 2.46 avg: 2.66 std dev: 0.8338 stddev: 1.0465 sample size: 15 sample size: 15 average number of ears peravg: 1.66 avg: 1.93 stalk std dev: 0.50709 std dev: 0.5936 sample size:15 sample size: 15 anthocyanin of brace roots absent absent stem, degreeof zig-zag absent or very absent or very slight slight stem, anthocyanincoloration absent or very absent or very of internodes weak weak ratioheight of insertion of medium medium peduncle of upper ear to plantlength 4. Leaf shape of apex pointed rounded undulation of margin ofblade intermediate intermediate width of blade wide wide curvature ofblade slightly moderately recurved recurved width of ear node leaf (cm)avg: 8.93 avg: 9.58 std dev: 0.4577 std dev: 0.7532 sample size: 15sample size: 15 length of ear node leaf (cm) avg: 77.2 avg: 77.4 stddev: 3.5143 std dev: 3.8601 sample size: 15 sample size: 15 number ofleaves above top avg: 5.73 avg: 6.06 ear std dev: 0.5936 std dev: 0.7988sample size: 15 sample size: 15 degrees leaf angle (second leaf 40° 55°above ear at anthesis to stalk above leaf) angle between blade and stemsmall (±25°) medium (±50°) (leaf just above upper ear) color (Munsellcolor chart 5GY 4/4 5GY 3/4 code) intensity of green color dark darksheath pubescence (scale from 9 8 1 (none) to 9 (like peach fuzz))marginal waves (scale from 1 7 8 (none) to 9 (many)) longitudinalcreases (scale 3 4 from 1 (none) to 9 (many)) anthocyanin coloration ofabsent or very absent or very sheath (first leaf) weak weak anthocyanincoloration of absent or very absent or very sheath (middle of plant)weak weak peduncle length medium very long 5. Tassel number of primarylateral avg: 30.9 avg: 20.13 branches std dev: 3.9364 std dev: 3.889sample size: 15 sample size: 15 branch angle from central avg: 24° avg:55.7° spike std dev: 16.3881° std dev: 9.037° sample size: 15 samplesize: 15 tassel length (top leaf collar to avg: 38.46 avg: 37.86 tasseltip) (cm) std dev: 1.302 std dev: 2.612 sample size: 15 sample size: 15density of spikeletes moderately dense moderately dense pollen shed(scale from 0 3 8 (male sterile) to 9 (heavy shed)) anther color(Munsell color 2.5GY 7/6 2.5GY 7/6 chart code) anthocyanin coloration ofabsent or very absent or very anthers (middle third of main weak weakaxis) glume color (Munsell color 2.5GY 8/6 5GY 6/8 chart code) barglumes (glume bands) absent absent anthocyanin coloration at base absentor very absent or very of glume (middle third of main weak weak axis)anthocyanin coloration of absent or very absent or very glume (excludingbase) weak weak time of anthesis (middle third very early to early tomedium of main axis, 50% of plants) early angle between main axis andsmall (±25°) medium (±50°) lateral branches (lower third of tassel)curvature of lateral branches absent or very moderately (lower third oftassel) slightly recurved recurved number of primary lateral many mediumbranches length of main axis above long very long lowest lateral branchlength of main axis above short short highest lateral branch length oflateral branch medium medium 6. Ear length very long very long diameter(middle) large large shape conico- cylindrical cylindrical time of silkemergence (50% early early of plants) anthocyanin coloration of silksabsent or very absent or very weak weak silk color (unhusked) (Munsell2.5GY 8/4 2.5GY 8/6 color chart code) (3 days after emergence) freshhusk color (unhusked) 5GY 7/6 2.5GY 7/6 (Munsell color chart code) (25days after 50% silking) husk tightness (unhusked) 8 6 (scale from 1(very loose) to 9 (very tight)) husk extension (unhusked) (at short(ears short (ears harvest) exposed) exposed) ear length (husked) (cm)avg: 21.85 avg: 24.75 std dev: 0.6236 std dev: 0.8271 sample size: 15sample size: 15 ear diameter at mid-point avg: 50.71 avg: 50 (husked)(mm) std dev: 4.0254 std dev: 1.727 sample size: 15 sample size: 15 earweight (husked) (g) avg: 345.53 avg: 369.46 std dev: 3.0675 std dev:41.026 sample size: 15 sample size: 15 number of kernel rows avg: 20.93avg: 16.6 (husked) std dev: 1.5796 std dev: 1.298 sample size: 15 samplesize: 15 kernel rows (husked) distinct distinct row alignment (husked)straight straight shank length (husked) (cm) avg: 14.32 avg: 17.9 stddev: 2.1452 std dev: 4.918 sample size: 15 sample size: 15 ear taper(husked) slight slight number of rows of grain many many number ofcolors of grains two one grain, intensity of yellow light dark colorgrain length medium medium grain width narrow narrow type of grain sweetsweet shrinkage of top of grain medium medium color of top of grainyellow yellow orange 7. Cob anthocyanin coloration of absent or veryabsent or very glumes of cob weak weak cob diameter at mid-point avg:32.45 avg: 31.50 (mm) std dev: 2.6109 std dev: 2.256 sample size: 15sample size: 15 cob color (Munsell color 158A 161D chart code) *Theseare typical values. Values may vary due to environment. Other valuesthat are substantially equivalent are within the scope of the invention.

TABLE 2 Physiological and Morphological Characteristics of Corn LineSHY-6S15-9078LP SHY-6S15- CHARACTERISTIC 9078LP FA 32 1. Type sweetsweet 2. Maturity in the Region of Best Adaptability emergence to 50% ofplants 63 days 63 days in silk 2418.7 heat units 2500.1 heat unitsemergence to 50% of plants 61 days 59 days in pollen 2338.6 heat units2326 heat units 10% to 90% pollen shed 5 days 4 days 227.1 heat units214.6 heat units 50% silk to optimum edible 24 days 21 days quality 1025heat units 890.6 heat units 3. Plant length (tassel included) shortshort plant height (to tassel tip) avg: 113.53 avg: 145.86 (cm) std dev:18.724 std dev: 5.777 sample size: 15 sample size: 15 ear height (tobase of top ear avg: 19.5 avg: 46.3 node) (cm) std dev: 8.2959 std dev:8.1871 sample size: 15 sample size: 15 length of top ear internode avg:7.5 avg: 12 (cm) std dev: 1.6611 std dev: 0.8259 sample size: 15 samplesize: 15 average number of tillers avg: 2.5 avg: 3 std dev: 1.187 stddev: 1.2536 sample size: 15 sample size: 15 average number of ears peravg: 1.86 avg: 2 stalk std dev: 0.5164 std dev: 0 sample size: 15 samplesize: 15 anthocyanin of brace roots absent absent stem, degree ofzig-zag absent or very slight slight stem, anthocyanin coloration absentor very absent or very of internodes weak weak ratio height of insertionof small medium peduncle of upper ear to plant length 4. Leaf shape ofapex pointed pointed undulation of margin of intermediate intermediateblade width of blade medium medium curvature of blade slightly recurvedslightly recurved width of ear node leaf (cm) avg: 9.0 avg: 7.36 stddev: 0.7326 std dev: 0.3498 sample size: 15 sample size: 15 length ofear node leaf (cm) avg: 57.6 avg: 69.76 std dev: 7.7917 std dev: 2.3058sample size: 15 sample size: 15 number of leaves above top avg: 6.4 avg:4.66 ear std dev: 1.5056 std dev: 0.7238 sample size: 15 sample size: 15degrees leaf angle (second 30° 37° leaf above ear at anthesis to stalkabove leaf) angle between blade and stem small (±25°) small (±25°) (leafjust above upper ear) color (Munsell color chart 7.5GY 3/4 5GY 3/4 code)intensity of green color dark medium sheath pubescence (scale 4 7 from 1(none) to 9 (like peach fuzz)) marginal waves (scale from 6 7 1 (none)to 9 (many)) longitudinal creases (scale 7 6 from 1 (none) to 9 (many))anthocyanin coloration of absent or very absent or very sheath (firstleaf) weak weak anthocyanin coloration of absent or very absent or verysheath (middle of plant) weak weak peduncle length medium medium 5.Tassel number of primary lateral avg: 31.8 avg: 15.4 branches std dev:7.771 std dev: 4.0673 sample size: 15 sample size: 15 branch angle fromcentral avg: 53.93° avg: 67° spike std dev: 13.3602° std dev: 13.2406°sample size: 15 sample size: 15 tassel length (top leaf collar avg: 30.3avg: 38.22 to tassel tip) (cm) std dev: 3.4527 std dev: 2.3098 samplesize: 15 sample size: 15 density of spikeletes moderately dense mediumpollen shed (scale from 0 8 7 (male sterile) to 9 (heavy shed)) anthercolor (Munsell color 2.5GY 7/4 2.5GY 8/8 chart code) anthocyanincoloration of absent or very absent or very anthers (middle third ofmain weak weak axis) glume color (Munsell color 5GY 5/2 5GY 6/4 chartcode) bar glumes (glume bands) absent absent anthocyanin coloration atabsent or very absent or very base of glume (middle third weak weak ofmain axis) anthocyanin coloration of absent or very absent or very glume(excluding base) weak weak time of anthesis (middle third late late ofmain axis, 50% of plants) angle between main axis and small (±25°) large(±75°) lateral branches (lower third of tassel) curvature of lateralbranches slightly strongly (lower third of tassel) recurved recurvednumber of primary lateral many medium branches length of main axis abovelong medium lowest lateral branch length of main axis above short shorthighest lateral branch length of lateral branch short very long 6. Earlength medium medium diameter (middle) medium medium shape cylindricalcylindrical time of silk emergence (50% early early of plants)anthocyanin coloration of absent or very absent or very silks weak weaksilk color (unhusked) 2.5GY 8/4 2.5GY 8/6 (Munsell color chart code) (3days after emergence) fresh husk color (unhusked) 5GY 6/6 2.5GY 8/6(Munsell color chart code) (25 days after 50% silking) husk tightness(unhusked) 8 8 (scale from 1 (very loose) to 9 (very tight)) huskextension (unhusked) medium (<8 cm) medium (<8 cm) (at harvest) earlength (husked) (cm) avg: 18.7 avg: 17.36 std dev: 2.5128 std dev:2.1336 sample size: 15 sample size: 15 ear diameter at mid-point avg:33.44 avg: 43.86 (husked) (mm) std dev: 8.709 std dev: 3.2361 samplesize: 15 sample size: 15 ear weight (husked) (g) avg: 172.26 avg: 153std dev: 32.605 std dev: 39.77 sample size: 15 sample size: 15 number ofkernel rows avg: 18.86 avg: 15.73 (husked) std dev: 1.407 std dev:1.9809 sample size: 15 sample size: 15 kernel rows (husked) distinctindistinct row alignment (husked) slightly curved slightly curved shanklength (husked) (cm) avg: 15.86 avg: 17.9 std dev: 3.6188 std dev:4.9034 sample size: 15 sample size: 15 ear taper (husked) average slightnumber of rows of grain medium medium number of colors of grains one onegrain, intensity of yellow light medium color grain length medium mediumgrain width medium narrow type of grain sweet sweet shrinkage of top ofgrain weak medium color of top of grain yellowish white yellow 7. Cobanthocyanin coloration of absent or very absent or very glumes of cobweak weak cob diameter at mid-point avg: 34.30 avg: 32.08 (mm) std dev:2.3113 std dev: 2.9177 sample size: 15 sample size: 15 cob color(Munsell color 160C 13B chart code) *These are typical values. Valuesmay vary due to environment. Other values that are substantiallyequivalent are within the scope of the invention.

TABLE 3 Physiological and Morphological Characteristics of Corn LineSHY-6RHBE322 SHY- CHARACTERISTIC 6RHBE322 FA 32 1. Type sweet sweet 2.Maturity in the Region of Best Adaptability emergence to 50% of 68 days63 days plants in silk 2609.1 heat units 2500.1 heat units emergence to50% of 61 days 59 days plants in pollen 2310.75 heat units 2326 heatunits 10% to 90% pollen shed 5 days 4 days 190.55 heat units 214.6 heatunits 50% silk to optimum 23 days 21 days edible quality 934.75 heatunits 890.6 heat units 3. Plant length (tassel included) medium shortplant height (to tassel tip) avg: 178.23 avg: 145.86 (cm) std dev:12.0532 std dev: 5.777 sample size: 15 sample size: 15 ear height (tobase of top avg: 57.9 avg: 46.3 ear node) (cm) std dev: 12.6267 std dev:8.1871 sample size: 15 sample size: 15 length of top ear internode avg:14.34 avg: 12 (cm) std dev: 1.0308 std dev: 0.8259 sample size: 15sample size: 15 average number of tillers avg: 1.4 avg: 3 std dev:1.0555 std dev: 1.2536 sample size: 15 sample size: 15 average number ofears avg: 1.6 avg: 2 per stalk std dev: 0.6324 std dev: 0 sample size:15 sample size: 15 anthocyanin of brace roots absent absent stem, degreeof zig-zag absent or very slight slight stem, anthocyanin colorationabsent or very absent or very of internodes weak weak ratio height ofinsertion of medium medium peduncle of upper ear to plant length 4. Leafshape of apex pointed pointed undulation of margin of intermediateintermediate blade width of blade medium medium curvature of bladeslightly recurved slightly recurved width of ear node leaf avg: 7.96avg: 7.36 (cm) std dev: 0.5207 std dev: 0.3498 sample size: 15 samplesize: 15 length of ear node leaf avg: 73.35 avg: 69.76 (cm) std dev:4.5998 std dev: 2.3058 sample size: 15 sample size: 15 number of leavesabove avg: 5.33 avg: 4.66 top ear std dev: 0.6172 std dev: 0.7238 samplesize: 15 sample size: 15 degrees leaf angle (second 42° 37° leaf aboveear at anthesis to stalk above leaf) angle between blade and small(±25°) small (±25°) stem (leaf just above upper ear) color (Munsellcolor chart 5GY 3/4 5GY 3/4 code) intensity of green color medium mediumsheath pubescence (scale 4 7 from 1 (none) to 9 (like peach fuzz))marginal waves (scale from 6 7 1 (none) to 9 (many)) longitudinalcreases (scale 5 6 from 1 (none) to 9 (many)) anthocyanin coloration ofabsent or very absent or very sheath (first leaf) weak weak anthocyanincoloration of absent or very absent or very sheath (middle of plant)weak weak peduncle length medium medium 5. Tassel number of primarylateral avg: 22.66 avg: 15.4 branches std dev: 7.4322 std dev: 4.0673sample size: 15 sample size: 15 branch angle from central avg: 40.2°avg: 67° spike std dev: 7.5517° std dev: 13.2406° sample size: 15 samplesize: 15 tassel length (top leaf avg: 30.46 avg: 38.22 collar to tasseltip) (cm) std dev: 2.665 std dev: 2.3098 sample size: 15 sample size: 15density of spikeletes medium medium pollen shed (scale from 0 7 7 (malesterile) to 9 (heavy shed)) anther color (Munsell 2.5GY 8/10 2.5GY 8/8color chart code) anthocyanin coloration of absent or very absent orvery anthers (middle third of weak weak main axis) glume color (Munsell2.5GY 6/4 5GY 6/4 color chart code) bar glumes (glume bands) absentabsent anthocyanin coloration at absent or very absent or very base ofglume (middle weak weak third of main axis) anthocyanin coloration ofabsent or very absent or very glume (excluding base) weak weak time ofanthesis (middle late late third of main axis, 50% of plants) anglebetween main axis and medium (±50°) large (±75°) lateral branches (lowerthird of tassel) curvature of lateral branches moderately strongly(lower third of tassel) recurved recurved number of primary lateralmedium medium branches length of main axis above very long medium lowestlateral branch length of main axis above long short highest lateralbranch length of lateral branch short very long 6. Ear length mediummedium diameter (middle) medium medium shape cylindrical cylindricaltime of silk emergence early to medium early (50% of plants) anthocyanincoloration of absent or very absent or very silks weak weak silk color(unhusked) 2.5GY 8/4 2.5GY 8/6 (Munsell color chart code) (3 days afteremergence) fresh husk color 5GY 7/6 2.5GY 8/6 (unhusked) (Munsell colorchart code) (25 days after 50% silking) husk tightness (unhusked) 8 8(scale from 1 (very loose) to 9 (very tight)) husk extension (unhusked)medium (<8 cm) medium (<8 cm) (at harvest) ear length (husked) (cm) avg:18.73 avg: 17.36 std dev: 0.8632 std dev: 2.1336 sample size: 15 samplesize: 15 ear diameter at mid-point avg: 43.18 avg: 43.86 (husked) (mm)std dev: 2.3075 std dev: 3.2361 sample size: 15 sample size: 15 earweight (husked) (g) avg: 156.8 avg: 153 std dev: 34.2604 std dev: 39.77sample size: 15 sample size: 15 number of kernel rows avg: 18.4 avg:15.73 (husked) std dev: 1.7237 std dev: 1.9809 sample size: 15 samplesize: 15 kernel rows (husked) indistinct indistinct row alignment(husked) slightly curved slightly curved shank length (husked) avg: 14.8avg: 17.9 (cm) std dev: 3.0434 std dev: 4.9034 sample size: 15 samplesize: 15 ear taper (husked) average slight number of rows of grainmedium medium number of colors of grains two one grain, intensity ofyellow medium medium color grain length medium medium grain width mediumnarrow type of grain sweet sweet shrinkage of top of grain strong mediumcolor of top of grain yellow yellow 7. Cob anthocyanin coloration ofabsent or very absent or very glumes of cob weak weak cob diameter atmid-point avg: 31.78 avg: 32.08 (mm) std dev: 2.8231 std dev: 2.9177sample size: 15 sample size: 15 cob color (Munsell color 158A 13B chartcode) *These are typical values. Values may vary due to environment.Other values that are substantially equivalent are within the scope ofthe invention.

C. Breeding Corn Plants

One aspect of the current invention concerns methods for producing seedof corn hybrid SVSK6143 involving crossing corn lines SHY-6S15-9078LPand SHY-6RHBE322. Alternatively, in other embodiments of the invention,hybrid SVSK6143, line SHY-6S15-9078LP, or line SHY-6RHBE322 may becrossed with itself or with any second plant. Such methods can be usedfor propagation of hybrid SVSK6143 and/or the corn lines SHY-6S15-9078LPand SHY-6RHBE322 or can be used to produce plants that are derived fromhybrid SVSK6143 and/or the corn lines SHY-6515-9078LP and SHY-6RHBE322.Plants derived from hybrid SVSK6143 and/or the corn linesSHY-6515-9078LP and SHY-6RHBE322 may be used, in certain embodiments,for the development of new corn varieties.

The development of new varieties using one or more starting varieties iswell known in the art. In accordance with the invention, novel varietiesmay be created by crossing a plant of the invention followed by multiplegenerations of breeding according to such well-known methods. Newvarieties may be created by crossing with any second plant. In selectingsuch a second plant to cross for the purpose of developing novel lines,it may be desired to choose those plants which either themselves exhibitone or more selected desirable characteristics or which exhibit thedesired characteristic(s) when in hybrid combination. Once initialcrosses have been made, inbreeding and selection take place to producenew varieties. For development of a uniform line, often five or moregenerations of selfing and selection are involved.

Uniform lines of new varieties may also be developed by way ofdouble-haploids. This technique allows the creation of true breedinglines without the need for multiple generations of selfing andselection. In this manner true breeding lines can be produced in aslittle as one generation. Haploid induction systems have been developedfor various plants to produce haploid tissues, plants and seeds. Thehaploid induction system can produce haploid plants from any genotype bycrossing with an inducer line. Inducer lines and methods for obtaininghaploid plants are known in the art.

Haploid embryos may be produced, for example, from microspores, pollen,anther cultures, or ovary cultures. The haploid embryos may then bedoubled autonomously, or by chemical treatments (e.g. colchicinetreatment). Alternatively, haploid embryos may be grown into haploidplants and treated to induce chromosome doubling. In either case,fertile homozygous plants are obtained. In accordance with theinvention, any of such techniques may be used in connection with a plantof the invention and progeny thereof to achieve a homozygous line.

Backcrossing can also be used to improve an inbred plant. Backcrossingtransfers a specific desirable trait from one inbred or non-inbredsource to an inbred that lacks that trait. This can be accomplished, forexample, by first crossing a superior inbred (A) (recurrent parent) to adonor inbred (non-recurrent parent), which carries the appropriate locusor loci for the trait in question. The progeny of this cross are thenmated back to the superior recurrent parent (A) followed by selection inthe resultant progeny for the desired trait to be transferred from thenon-recurrent parent. After five or more backcross generations withselection for the desired trait, the progeny have the characteristicbeing transferred, but are like the superior parent for most or almostall other loci. The last backcross generation would be selfed to givepure breeding progeny for the trait being transferred.

The plants of the present invention are particularly well suited for thedevelopment of new lines based on the elite nature of the geneticbackground of the plants. In selecting a second plant to cross withSVSK6143 and/or corn lines SHY-6S15-9078LP and SHY-6RHBE322 for thepurpose of developing novel corn lines, it will typically be preferredto choose those plants which either themselves exhibit one or moreselected desirable characteristics or which exhibit the desiredcharacteristic(s) when in hybrid combination. Examples of desirabletraits may include, in specific embodiments, male sterility, herbicideresistance, resistance for bacterial, fungal, or viral disease, insectresistance, male fertility, sugar content, and enhanced nutritionalquality.

D. Further Embodiments of the Invention

In certain aspects of the invention, plants described herein areprovided modified to include at least a first desired heritable trait.Such plants may, in one embodiment, be developed by a plant breedingtechnique called backcrossing, wherein essentially all of themorphological and physiological characteristics of a variety arerecovered in addition to a genetic locus transferred into the plant viathe backcrossing technique. The term single locus converted plant asused herein refers to those corn plants which are developed by a plantbreeding technique called backcrossing, wherein essentially all of themorphological and physiological characteristics of a variety arerecovered in addition to the single locus transferred into the varietyvia the backcrossing technique. By essentially all of the morphologicaland physiological characteristics, it is meant that the characteristicsof a plant are recovered that are otherwise present when compared in thesame environment, other than an occasional variant trait that mightarise during backcrossing or direct introduction of a transgene.

Backcrossing methods can be used with the present invention to improveor introduce a characteristic into the present variety. The parentalcorn plant which contributes the locus for the desired characteristic istermed the nonrecurrent or donor parent. This terminology refers to thefact that the nonrecurrent parent is used one time in the backcrossprotocol and therefore does not recur. The parental corn plant to whichthe locus or loci from the nonrecurrent parent are transferred is knownas the recurrent parent as it is used for several rounds in thebackcrossing protocol.

In a typical backcross protocol, the original variety of interest(recurrent parent) is crossed to a second variety (nonrecurrent parent)that carries the single locus of interest to be transferred. Theresulting progeny from this cross are then crossed again to therecurrent parent and the process is repeated until a corn plant isobtained wherein essentially all of the morphological and physiologicalcharacteristics of the recurrent parent are recovered in the convertedplant, in addition to the single transferred locus from the nonrecurrentparent.

The selection of a suitable recurrent parent is an important step for asuccessful backcrossing procedure. The goal of a backcross protocol isto alter or substitute a single trait or characteristic in the originalvariety. To accomplish this, a single locus of the recurrent variety ismodified or substituted with the desired locus from the nonrecurrentparent, while retaining essentially all of the rest of the desiredgenetic, and therefore the desired physiological and morphologicalconstitution of the original variety. The choice of the particularnonrecurrent parent will depend on the purpose of the backcross; one ofthe major purposes is to add some commercially desirable trait to theplant. The exact backcrossing protocol will depend on the characteristicor trait being altered and the genetic distance between the recurrentand nonrecurrent parents. Although backcrossing methods are simplifiedwhen the characteristic being transferred is a dominant allele, arecessive allele, or an additive allele (between recessive anddominant), may also be transferred. In this instance it may be necessaryto introduce a test of the progeny to determine if the desiredcharacteristic has been successfully transferred.

In one embodiment, progeny corn plants of a backcross in which a plantdescribed herein is the recurrent parent comprise (i) the desired traitfrom the non-recurrent parent and (ii) all of the physiological andmorphological characteristics of corn the recurrent parent as determinedat the 5% significance level when grown in the same environmentalconditions.

New varieties can also be developed from more than two parents. Thetechnique, known as modified backcrossing, uses different recurrentparents during the backcrossing. Modified backcrossing may be used toreplace the original recurrent parent with a variety having certain moredesirable characteristics or multiple parents may be used to obtaindifferent desirable characteristics from each.

With the development of molecular markers associated with particulartraits, it is possible to add additional traits into an established germline, such as represented here, with the end result being substantiallythe same base germplasm with the addition of a new trait or traits.Molecular breeding, as described in Moose and Mumm, 2008 (PlantPhysiol., 147: 969-977), for example, and elsewhere, provides amechanism for integrating single or multiple traits or QTL into an eliteline. This molecular breeding-facilitated movement of a trait or traitsinto an elite line may encompass incorporation of a particular genomicfragment associated with a particular trait of interest into the eliteline by the mechanism of identification of the integrated genomicfragment with the use of flanking or associated marker assays. In theembodiment represented here, one, two, three or four genomic loci, forexample, may be integrated into an elite line via this methodology. Whenthis elite line containing the additional loci is further crossed withanother parental elite line to produce hybrid offspring, it is possibleto then incorporate at least eight separate additional loci into thehybrid. These additional loci may confer, for example, such traits as adisease resistance or a fruit quality trait. In one embodiment, eachlocus may confer a separate trait. In another embodiment, loci may needto be homozygous and exist in each parent line to confer a trait in thehybrid. In yet another embodiment, multiple loci may be combined toconfer a single robust phenotype of a desired trait.

Many single locus traits have been identified that are not regularlyselected for in the development of a new inbred but that can be improvedby backcrossing techniques. Single locus traits may or may not betransgenic; examples of these traits include, but are not limited to,male sterility, waxy starch, herbicide resistance, resistance tobacterial, fungal, or viral disease, insect resistance, sugar content,male fertility and enhanced nutritional quality. These genes aregenerally inherited through the nucleus, but may be inherited throughthe cytoplasm. Some known exceptions to this are genes for malesterility, some of which are inherited cytoplasmically, but still act asa single locus trait.

Direct selection may be applied where the single locus acts as adominant trait. For this selection process, the progeny of the initialcross are assayed for viral resistance and/or the presence of thecorresponding gene prior to the backcrossing. Selection eliminates anyplants that do not have the desired gene and resistance trait, and onlythose plants that have the trait are used in the subsequent backcross.This process is then repeated for all additional backcross generations.

Selection of corn plants for breeding is not necessarily dependent onthe phenotype of a plant and instead can be based on geneticinvestigations. For example, one can utilize a suitable genetic markerwhich is closely genetically linked to a trait of interest. One of thesemarkers can be used to identify the presence or absence of a trait inthe offspring of a particular cross and can be used in selection ofprogeny for continued breeding. This technique is commonly referred toas marker assisted selection. Any other type of genetic marker or otherassay which is able to identify the relative presence or absence of atrait of interest in a plant can also be useful for breeding purposes.Procedures for marker assisted selection are well known in the art. Suchmethods will be of particular utility in the case of recessive traitsand variable phenotypes, or where conventional assays may be moreexpensive, time consuming or otherwise disadvantageous. Types of geneticmarkers which could be used in accordance with the invention include,but are not necessarily limited to, Simple Sequence Length Polymorphisms(SSLPs) (Williams et al., Nucleic Acids Res., 1 8:6531-6535, 1990),Randomly Amplified Polymorphic DNAs (RAPDs), DNA AmplificationFingerprinting (DAF), Sequence Characterized Amplified Regions (SCARs),Arbitrary Primed Polymerase Chain Reaction (AP-PCR), Amplified FragmentLength Polymorphisms (AFLPs) (EP 534 858, specifically incorporatedherein by reference in its entirety), and Single NucleotidePolymorphisms (SNPs) (Wang et al., Science, 280:1077-1082, 1998).

E. Plants Derived by Genetic Engineering

Many useful traits that can be introduced by backcrossing, as well asdirectly into a plant, are those which are introduced by moleculargenetic methods. Such methods include, but are not limited to, variousplant transformation techniques and methods for site-specificrecombination, the use of which are well-known in the art, and include,for example, the CRISPR-Cas system, zinc-finger nucleases (ZFNs), andtranscription activator-like effector nucleases (TALENs), among others.

In one embodiment of the invention, genetic transformation may be usedto insert a selected transgene into a plant of the invention or may,alternatively, be used for the preparation of transgenes which can beintroduced by backcrossing. Methods for the transformation of plantsthat are well-known to those of skill in the art and applicable to manycrop species include, but are not limited to, electroporation,microprojectile bombardment, Agrobacterium-mediated transformation, anddirect DNA uptake by protoplasts.

To effect transformation by electroporation, one may employ eitherfriable tissues, such as a suspension culture of cells or embryogeniccallus or alternatively one may transform immature embryos or otherorganized tissue directly. In this technique, one would partiallydegrade the cell walls of the chosen cells by exposing them topectin-degrading enzymes (pectolyases) or mechanically wound tissues ina controlled manner.

An efficient method for delivering transforming DNA segments to plantcells is microprojectile bombardment. In this method, particles arecoated with nucleic acids and delivered into cells by a propellingforce. Exemplary particles include those comprised of tungsten,platinum, and, preferably, gold. For the bombardment, cells insuspension are concentrated on filters or solid culture medium.Alternatively, immature embryos or other target cells may be arranged onsolid culture medium. The cells to be bombarded are positioned at anappropriate distance below the macroprojectile stopping plate.

An illustrative embodiment of a method for delivering DNA into plantcells by acceleration is the Biolistics Particle Delivery System, whichcan be used to propel particles coated with DNA or cells through ascreen, such as a stainless steel or Nytex screen, onto a surfacecovered with target cells. The screen disperses the particles so thatthey are not delivered to the recipient cells in large aggregates.Microprojectile bombardment techniques are widely applicable and may beused to transform virtually any plant species.

Agrobacterium-mediated transfer is another widely applicable system forintroducing gene loci into plant cells. An advantage of the technique isthat DNA can be introduced into whole plant tissues, thereby bypassingthe need for regeneration of an intact plant from a protoplast. ModernAgrobacterium transformation vectors are capable of replication in E.coli as well as Agrobacterium, allowing for convenient manipulations(Klee et al., Nat. Biotechnol., 3(7):637-642, 1985). Moreover, recenttechnological advances in vectors for Agrobacterium-mediated genetransfer have improved the arrangement of genes and restriction sites inthe vectors to facilitate the construction of vectors capable ofexpressing various polypeptide coding genes. The vectors described haveconvenient multi-linker regions flanked by a promoter and apolyadenylation site for direct expression of inserted polypeptidecoding genes. Additionally, Agrobacterium containing both armed anddisarmed Ti genes can be used for transformation.

In those plant strains where Agrobacterium-mediated transformation isefficient, it is the method of choice because of the facile and definednature of the gene locus transfer. The use of Agrobacterium-mediatedplant integrating vectors to introduce DNA into plant cells is wellknown in the art (Fraley et al., Nat. Biotechnol., 3:629-635, 1985; U.S.Pat. No. 5,563,055).

Transformation of plant protoplasts also can be achieved using methodsbased on calcium phosphate precipitation, polyethylene glycol treatment,electroporation, and combinations of these treatments (see, e.g.,Potrykus et al., Mol. Gen. Genet., 199:183-188, 1985; Omirulleh et al.,Plant Mol. Biol., 21(3):415-428, 1993; Fromm et al., Nature,312:791-793, 1986; Uchimiya et al., Mol. Gen. Genet., 204:204, 1986;Marcotte et al., Nature, 335:454, 1988). Transformation of plants andexpression of foreign genetic elements is exemplified in Choi et al.(Plant Cell Rep., 13: 344-348, 1994) and Ellul et al. (Theor. Appl.Genet., 107:462-469, 2003).

A number of promoters have utility for plant gene expression for anygene of interest including but not limited to selectable markers,scoreable markers, genes for pest tolerance, disease resistance,nutritional enhancements and any other gene of agronomic interest.Examples of constitutive promoters useful for plant gene expressioninclude, but are not limited to, the cauliflower mosaic virus (CaMV)P-35S promoter, which confers constitutive, high-level expression inmost plant tissues (see, e.g., Odel et al., Nature, 313:810, 1985),including in monocots (see, e.g., Dekeyser et al., Plant Cell, 2:591,1990; Terada and Shimamoto, Mol. Gen. Genet., 220:389, 1990); a tandemlyduplicated version of the CaMV 35S promoter, the enhanced 35S promoter(P-e35S); the nopaline synthase promoter (An et al., Plant Physiol.,88:547, 1988); the octopine synthase promoter (Fromm et al., Plant Cell,1:977, 1989); and the figwort mosaic virus (P-FMV) promoter as describedin U.S. Pat. No. 5,378,619 and an enhanced version of the FMV promoter(P-eFMV) where the promoter sequence of P-FMV is duplicated in tandem;the cauliflower mosaic virus 19S promoter; a sugarcane bacilliform viruspromoter; a commelina yellow mottle virus promoter; and other plant DNAvirus promoters known to express in plant cells.

A variety of plant gene promoters that are regulated in response toenvironmental, hormonal, chemical, and/or developmental signals can alsobe used for expression of an operably linked gene in plant cells,including promoters regulated by (1) heat (Callis et al., PlantPhysiol., 88:965, 1988), (2) light (e.g., pea rbcS-3A promoter,Kuhlemeier et al., Plant Cell, 1:471, 1989; maize rbcS promoter,Schaffner and Sheen, Plant Cell, 3:997, 1991; or chlorophyll a/b-bindingprotein promoter, Simpson et al., EMBO J., 4:2723, 1985), (3) hormones,such as abscisic acid (Marcotte et al., Plant Cell, 1:969, 1989), (4)wounding (e.g., wunl, Siebertz et al., Plant Cell, 1:961, 1989); or (5)chemicals such as methyl jasmonate, salicylic acid, or Safener. It mayalso be advantageous to employ organ-specific promoters (e.g., Roshal etal., EMBO J., 6:1155, 1987; Schernthaner et al., EMBO J., 7:1249, 1988;Bustos et al., Plant Cell, 1:839, 1989).

Exemplary nucleic acids which may be introduced to plants of thisinvention include, for example, DNA sequences or genes from anotherspecies, or even genes or sequences which originate with or are presentin the same species, but are incorporated into recipient cells bygenetic engineering methods rather than classical reproduction orbreeding techniques. However, the term “exogenous” is also intended torefer to genes that are not normally present in the cell beingtransformed, or perhaps simply not present in the form, structure, etc.,as found in the transforming DNA segment or gene, or genes which arenormally present and that one desires to express in a manner thatdiffers from the natural expression pattern, e.g., to over-express.Thus, the term “exogenous” gene or DNA is intended to refer to any geneor DNA segment that is introduced into a recipient cell, regardless ofwhether a similar gene may already be present in such a cell. The typeof DNA included in the exogenous DNA can include DNA which is alreadypresent in the plant cell, DNA from another plant, DNA from a differentorganism, or a DNA generated externally, such as a DNA sequencecontaining an antisense message of a gene, or a DNA sequence encoding asynthetic or modified version of a gene.

Many hundreds if not thousands of different genes are known and couldpotentially be introduced into a corn plant according to the invention.Non-limiting examples of particular genes and corresponding phenotypesone may choose to introduce into a corn plant include one or more genesfor insect tolerance, such as a Bacillus thuringiensis (B.t.) gene, pesttolerance such as genes for fungal disease control, herbicide tolerancesuch as genes conferring glyphosate tolerance and genes for qualityimprovements such as yield, nutritional enhancements, environmental orstress tolerances, or any desirable changes in plant physiology, growth,development, morphology or plant product(s). For example, structuralgenes would include any gene that confers insect tolerance including butnot limited to a Bacillus insect control protein gene as described in WO99/31248, herein incorporated by reference in its entirety, U.S. Pat.No. 5,689,052, herein incorporated by reference in its entirety, U.S.Pat. Nos. 5,500,365 and 5,880,275, herein incorporated by reference intheir entirety. In another embodiment, the structural gene can confertolerance to the herbicide glyphosate as conferred by genes including,but not limited to Agrobacterium strain CP4 glyphosate resistant EPSPSgene (aroA:CP4) as described in U.S. Pat. No. 5,633,435, hereinincorporated by reference in its entirety, or glyphosate oxidoreductasegene (GOX) as described in U.S. Pat. No. 5,463,175, herein incorporatedby reference in its entirety.

Alternatively, the DNA coding sequences can affect these phenotypes byencoding a non-translatable RNA molecule that causes the targetedinhibition of expression of an endogenous gene, for example viaantisense- or cosuppression-mediated mechanisms (see, for example, Birdet al., Biotech. Gen. Engin. Rev., 9:207, 1991). The RNA could also be acatalytic RNA molecule (i.e., a ribozyme) engineered to cleave a desiredendogenous mRNA product (see for example, Gibson and Shillito, Mol.Biotech., 7:125, 1997). Thus, any gene which produces a protein or mRNAwhich expresses a phenotype or morphology change of interest is usefulfor the practice of the present invention.

F. Male Sterility

Examples of genes conferring male sterility include those disclosed inU.S. Pat. Nos. 3,861,709, 3,710,511, 4,654,465, 5,625,132, and4,727,219, each of the disclosures of which are specificallyincorporated herein by reference in their entirety. Male sterility genescan increase the efficiency with which hybrids are made, in that theyeliminate the need to physically emasculate the corn plant used as afemale in a given cross.

Where one desires to employ male-sterility systems with a corn plant inaccordance with the invention, it may be beneficial to also utilize oneor more male-fertility restorer genes. For example, where cytoplasmicmale sterility (CMS) is used, hybrid seed production requires threeinbred lines: (1) a cytoplasmically male-sterile line having a CMScytoplasm; (2) a fertile inbred with normal cytoplasm, which is isogenicwith the CMS line for nuclear genes (“maintainer line”); and (3) adistinct, fertile inbred with normal cytoplasm, carrying a fertilityrestoring gene (“restorer” line). The CMS line is propagated bypollination with the maintainer line, with all of the progeny being malesterile, as the CMS cytoplasm is derived from the female parent. Thesemale sterile plants can then be efficiently employed as the femaleparent in hybrid crosses with the restorer line, without the need forphysical emasculation of the male reproductive parts of the femaleparent.

The presence of a male-fertility restorer gene results in the productionof fully fertile F₁ hybrid progeny. If no restorer gene is present inthe male parent, male-sterile hybrids are obtained. Such hybrids areuseful where the vegetative tissue of the corn plant is utilized, e.g.,for silage, but in most cases, the seeds will be deemed the mostvaluable portion of the crop, so fertility of the hybrids in these cropsmust be restored. Therefore, one aspect of the current inventionconcerns a corn plant of the invention comprising a genetic locuscapable of restoring male fertility in an otherwise male-sterile plant.Examples of male-sterility genes and corresponding restorers which couldbe employed with the plants of the invention are well known to those ofskill in the art of plant breeding and are disclosed in, for instance,U.S. Pat. Nos. 5,530,191; 5,689,041; 5,741,684; and 5,684,242, thedisclosures of which are each specifically incorporated herein byreference in their entirety.

G. Herbicide Resistance

Numerous herbicide resistance genes are known and may be employed withthe invention. An example is a gene conferring resistance to a herbicidethat inhibits the growing point or meristem, such as an imidazalinone ora sulfonylurea. Exemplary genes in this category code for mutant ALS andAHAS enzyme as described, for example, by Lee et al., EMBO J., 7:1241,1988; Gleen et al., Plant Molec. Biology, 18:1185-1187, 1992; and Mikiet al., Theor. Appl. Genet., 80:449, 1990.

Resistance genes for glyphosate (resistance conferred by mutant5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) and aroA genes,respectively), and hygromycin B phosphotransferase, and to otherphosphono compounds such as glufosinate (phosphinothricin acetyltransferase (PAT) and Streptomyces hygroscopicus phosphinothricin-acetyltransferase (bar) genes) may also be used. See, for example, U.S. Pat.No. 4,940,835 to Shah et al., which discloses the nucleotide sequence ofa form of EPSPS which can confer glyphosate resistance. A DNA moleculeencoding a mutant aroA gene can be obtained under ATCC accession number39256, and the nucleotide sequence of the mutant gene is disclosed inU.S. Pat. No. 4,769,061 to Comai. A hygromycin B phosphotransferase genefrom E. coli that confers resistance to glyphosate in tobacco callus andplants is described in Penaloza-Vazquez et al. (Plant Cell Reports,14:482-487, 1995). European patent application No. 0 333 033 to Kumadaet al., and U.S. Pat. No. 4,975,374 to Goodman et al., disclosenucleotide sequences of glutamine synthetase genes which conferresistance to herbicides such as L-phosphinothricin. The nucleotidesequence of a phosphinothricin-acetyltransferase gene is provided inEuropean application No. 0 242 246 to Leemans et al. DeGreef et al.,(Biotechnology, 7:61, 1989), describe the production of transgenicplants that express chimeric bar genes coding for phosphinothricinacetyl transferase activity. Exemplary of genes conferring resistance tophenoxy propionic acids and cyclohexanediones, such as sethoxydim andhaloxyfop are the Acct-S1, Accl-S2 and Acct-S3 genes described byMarshall et al., (Theor. Appl. Genet., 83:4:35, 1992).

Genes conferring resistance to a herbicide that inhibits photosynthesisare also known, such as a triazine (psbA and gs+ genes) and abenzonitrile (nitrilase gene). Przibilla et al., (Plant Cell, 3:169,1991), describe the transformation of Chlamydomonas with plasmidsencoding mutant psbA genes. Nucleotide sequences for nitrilase genes aredisclosed in U.S. Pat. No. 4,810,648 to Stalker, and DNA moleculescontaining these genes are available under ATCC Accession Nos. 53435,67441, and 67442. Cloning and expression of DNA coding for a glutathioneS-transferase is described by Hayes et al., (Biochem. J., 285(Pt1):173-180, 1992). Protoporphyrinogen oxidase (PPO) is the target of thePPO-inhibitor class of herbicides; a PPO-inhibitor resistant PPO genewas recently identified in Amaranthus tuberculatus (Patzoldt et al.,PNAS, 103(33):12329-2334, 2006). The herbicide methyl viologen inhibitsCO₂ assimilation. Foyer et al. (Plant Physiol., 109:1047-1057, 1995)describe a plant overexpressing glutathione reductase (GR) which isresistant to methyl viologen treatment.

Siminszky (Phytochemistry Reviews, 5:445-458, 2006) describes plantcytochrome P450-mediated detoxification of multiple, chemicallyunrelated classes of herbicides.

H. Waxy Starch

The waxy characteristic is an example of a recessive trait. In thisexample, the progeny resulting from the first backcross generation (BC1)must be grown and selfed. A test is then run on the selfed seed from theBC1 plant to determine which BC1 plants carried the recessive gene forthe waxy trait. In other recessive traits additional progeny testing,for example growing additional generations such as the BC1S1, may berequired to determine which plants carry the recessive gene.

I. Disease Resistance

Plant defenses are often activated by specific interaction between theproduct of a disease resistance gene (R) in the plant and the product ofa corresponding avirulence (Avr) gene in the pathogen. A plant line canbe transformed with a cloned resistance gene to engineer plants that areresistant to specific pathogen strains. See, for example, Jones et al.,Science, 266:7891, 1994 (cloning of the tomato Cf-9 gene for resistanceto Cladosporium flavum); Martin et al., Science, 262: 1432, 1993 (tomatoPto gene for resistance to Pseudomonas syringae pv.); and Mindrinos etal., Cell, 78(6):1089-1099, 1994 (Arabidopsis RPS2 gene for resistanceto Pseudomonas syringae).

A viral-invasive protein or a complex toxin derived therefrom may alsobe used for viral disease resistance. For example, the accumulation ofviral coat proteins in transformed plant cells imparts resistance toviral infection and/or disease development effected by the virus fromwhich the coat protein gene is derived, as well as by related viruses.See Beachy et al., (Ann. Rev. Phytopathol., 28:451, 1990). Coatprotein-mediated resistance has been conferred upon transformed plantsagainst alfalfa mosaic virus, cucumber mosaic virus, tobacco streakvirus, potato virus X, potato virus Y, tobacco etch virus, tobaccorattle virus and tobacco mosaic virus. Id.

A virus-specific antibody may also be used. See, for example,Tavladoraki et al., (Nature, 366:469, 1993), who show that transgenicplants expressing recombinant antibody genes are protected from virusattack. Additional means of inducing whole-plant resistance to apathogen include modulation of the systemic acquired resistance (SAR) orpathogenesis related (PR) genes, for example genes homologous to theArabidopsis thaliana NIM1/NPR1/SAI1, and/or by increasing salicylic acidproduction (Ryals et al., Plant Cell, 8:1809-1819, 1996).

Logemann et al., (Biotechnology, 10:305, 1992), for example, disclosetransgenic plants expressing a barley ribosome-inactivating gene have anincreased resistance to fungal disease. Plant defensins may be used toprovide resistance to fungal pathogens (Thomma et al., Planta,216:193-202, 2002). Other examples of fungal disease resistance areprovided in U.S. Pat. Nos. 6,653,280; 6,573,361; 6,506,962; 6,316,407;6,215,048; 5,516,671; 5,773,696; 6,121,436; 6,316,407; and 6,506,962.

J. Insect Resistance

One example of an insect resistance gene includes a Bacillusthuringiensis (Bt) protein, a derivative thereof or a syntheticpolypeptide modeled thereon. See, for example, Geiser et al., (Gene,48:109-118, 1986), who disclose the cloning and nucleotide sequence of aBt δ-endotoxin gene. Moreover, DNA molecules encoding δ-endotoxin genescan be purchased from the American Type Culture Collection, Manassas,Va., for example, under ATCC Accession Nos. 40098, 67136, 31995 and31998. Another example is a lectin. See, for example, Van Damme et al.,(Plant Molec. Biol., 24:25, 1994), who disclose the nucleotide sequencesof several Clivia miniata mannose-binding lectin genes. Avitamin-binding protein may also be used, such as avidin. See PCTapplication US93/06487, the contents of which are hereby incorporated byreference. This application teaches the use of avidin and avidinhomologues as larvicides against insect pests.

Yet another insect resistance gene is an enzyme inhibitor, for example,a protease or proteinase inhibitor or an amylase inhibitor. See, forexample, Abe et al., (J. Biol. Chem., 262:16793, 1987) (nucleotidesequence of rice cysteine proteinase inhibitor), Huub et al., (PlantMolec. Biol., 21:985, 1993) (nucleotide sequence of cDNA encodingtobacco proteinase inhibitor I), and Sumitani et al., (Biosci. Biotech.Biochem., 57:1243, 1993) (nucleotide sequence of Streptomycesnitrosporeus α-amylase inhibitor).

An insect-specific hormone or pheromone may also be used. See, forexample, the disclosure by Hammock et al., (Nature, 344:458, 1990), ofbaculovirus expression of cloned juvenile hormone esterase, aninactivator of juvenile hormone, Gade and Goldsworthy (Eds.Physiological System in Insects, Elsevier Academic Press, Burlington,Mass., 2007), describing allostatins and their potential use in pestcontrol; and Palli et al., (Vitam. Horm., 73:59-100, 2005), disclosinguse of ecdysteroid and ecdysteroid receptor in agriculture. The diuretichormone receptor (DHR) was identified in Price et al., (Insect Mol.Biol., 13:469-480, 2004) as a candidate target of insecticides.

Still other examples include an insect-specific antibody or animmunotoxin derived therefrom and a developmental-arrestive protein. SeeTaylor et al., (Seventh Int'l Symposium on Molecular Plant-MicrobeInteractions, Edinburgh, Scotland, Abstract W97, 1994), who describedenzymatic inactivation in transgenic tobacco via production ofsingle-chain antibody fragments.

Nematode resistance has been described, for example, in U.S. Pat. No.6,228,992 and bacterial disease resistance in U.S. Pat. No. 5,516,671.

K. Modified Fatty Acid, Phytate, and Carbohydrate Metabolism

Genes may be used conferring modified fatty acid metabolism. Forexample, stearyl-ACP desaturase genes may be used. See Knutzon et al.,(Proc. Natl. Acad. Sci. USA, 89:2624, 1992). Various fatty aciddesaturases have also been described, such as a Saccharomyces cerevisiaeOLE1 gene encoding Δ9 fatty acid desaturase, an enzyme which forms themonounsaturated palmitoleic (16:1) and oleic (18:1) fatty acids frompalmitoyl (16:0) or stearoyl (18:0) CoA (McDonough et al., J. Biol.Chem., 267(9):5931-5936, 1992); a gene encoding a stearoyl-acyl carrierprotein delta-9 desaturase from castor (Fox et al., Proc. Natl. Acad.Sci. USA, 90(6):2486-2490, 1993); Δ6- and Δ12-desaturases from thecyanobacteria Synechocystis responsible for the conversion of linoleicacid (18:2) to gamma-linolenic acid (18:3 gamma) (Reddy et al., PlantMol. Biol., 22(2):293-300, 1993); a gene from Arabidopsis thaliana thatencodes an omega-3 desaturase (Arondel et al., Science,258(5086):1353-1355 1992); plant Δ9-desaturases (PCT Application Publ.No. WO 91/13972) and soybean and Brassica Δ15 desaturases (EuropeanPatent Application Publ. No. EP 0616644).

Phytate metabolism may also be modified by introduction of aphytase-encoding gene to enhance breakdown of phytate, adding more freephosphate to the transformed plant. For example, see Van Hartingsveldtet al., (Gene, 127:87, 1993), for a disclosure of the nucleotidesequence of an Aspergillus niger phytase gene. In corn, this, forexample, could be accomplished by cloning and then reintroducing DNAassociated with the single allele which is responsible for corn mutantscharacterized by low levels of phytic acid. See Raboy et al., PlantPhysiol., 124(1):355-368, 1990.

A number of genes are known that may be used to alter carbohydratemetabolism. For example, plants may be transformed with a gene codingfor an enzyme that alters the branching pattern of starch. See Shirozaet al., (J. Bacteriol., 170:810, 1988) (nucleotide sequence ofStreptococcus mutans fructosyltransferase gene), Steinmetz et al., (Mol.Gen. Genet., 20:220, 1985) (nucleotide sequence of Bacillus subtilislevansucrase gene), Pen et al., (Biotechnology, 10:292, 1992)(production of transgenic plants that express Bacillus licheniformisα-amylase), Elliot et al., (Plant Molec. Biol., 21:515, 1993)(nucleotide sequences of tomato invertase genes), Sergaard et al., (J.Biol. Chem., 268:22480, 1993) (site-directed mutagenesis of barleyα-amylase gene), and Fisher et al., (Plant Physiol., 102:1045, 1993)(maize endosperm starch branching enzyme II). The Z10 gene encoding a 10kD zein storage protein from maize may also be used to alter thequantities of 10 kD zein in the cells relative to other components(Kirihara et al., Gene, 71(2):359-370, 1988).

U.S. Pat. No. 6,930,225 describes maize cellulose synthase genes andmethods of use thereof.

L. Resistance to Abiotic Stress

Abiotic stress includes dehydration or other osmotic stress, salinity,high or low light intensity, high or low temperatures, submergence,exposure to heavy metals, and oxidative stress.Delta-pyrroline-5-carboxylate synthetase (P5CS) from mothbean has beenused to provide protection against general osmotic stress.Mannitol-1-phosphate dehydrogenase (mt1D) from E. coli has been used toprovide protection against drought and salinity. Choline oxidase (codAfrom Arthrobactor globiformis) can protect against cold and salt. E.coli choline dehydrogenase (betA) provides protection against salt.Additional protection from cold can be provided by omega-3-fatty aciddesaturase (fad7) from Arabidopsis thaliana. Trehalose-6-phosphatesynthase and levan sucrase (SacB) from yeast and Bacillus subtilis,respectively, can provide protection against drought (summarized fromAnnex II Genetic Engineering for Abiotic Stress Tolerance in Plants,Consultative Group On International Agricultural Research TechnicalAdvisory Committee). Overexpression of superoxide dismutase can be usedto protect against superoxides, as described in U.S. Pat. No. 5,538,878to Thomas et al.

M. Additional Traits

Additional traits can be introduced into a corn variety of the presentinvention. A non-limiting example of such a trait is a coding sequencewhich decreases RNA and/or protein levels. The decreased RNA and/orprotein levels may be achieved through RNAi methods, such as thosedescribed in U.S. Pat. No. 6,506,559 to Fire and Mellow.

Another trait that may find use with the corn variety of the inventionis a sequence which allows for site-specific recombination. Examples ofsuch sequences include the FRT sequence, used with the FLP recombinase(Zhu and Sadowski, J. Biol. Chem., 270:23044-23054, 1995); and the LOXsequence, used with CRE recombinase (Sauer, Mol. Cell. Biol.,7:2087-2096, 1987). The recombinase genes can be encoded at any locationwithin the genome of the corn plant, and are active in the hemizygousstate.

It may also be desirable to make corn plants more tolerant to or moreeasily transformed with Agrobacterium tumefaciens. Expression of p53 andiap, two baculovirus cell-death suppressor genes, inhibited tissuenecrosis and DNA cleavage. Additional targets can include plant-encodedproteins that interact with the Agrobacterium Vir genes; enzymesinvolved in plant cell wall formation; and histones, histoneacetyltransferases and histone deacetylases (reviewed in Gelvin,Microbiology & Mol. Biol. Reviews, 67:16-37, 2003).

In addition to the modification of oil, fatty acid or phytate contentdescribed above, it may additionally be beneficial to modify the amountsor levels of other compounds. For example, the amount or composition ofantioxidants can be altered. See, for example, U.S. Pat. Nos. 6,787,618and 7,154,029 and International Patent Appl. Pub. No. WO 00/68393, whichdisclose the manipulation of antioxidant levels, and InternationalPatent Appl. Pub. No. WO 03/082899, which discloses the manipulation ofan antioxidant biosynthetic pathway.

Additionally, seed amino acid content may be manipulated. U.S. Pat. No.5,850,016 and International Patent Appl. Pub. No. WO 99/40209 disclosethe alteration of the amino acid compositions of seeds. U.S. Pat. Nos.6,080,913 and 6,127,600 disclose methods of increasing accumulation ofessential amino acids in seeds.

U.S. Pat. No. 5,559,223 describes synthetic storage proteins in whichthe levels of essential amino acids can be manipulated. InternationalPatent Appl. Pub. No. WO 99/29882 discloses methods for altering aminoacid content of proteins. International Patent Appl. Pub. No. WO98/20133 describes proteins with enhanced levels of essential aminoacids. International Patent Appl. Pub. No. WO 98/56935 and U.S. Pat.Nos. 6,346,403, 6,441,274 and 6,664,445 disclose plant amino acidbiosynthetic enzymes. International Patent Appl. Pub. No. WO 98/45458describes synthetic seed proteins having a higher percentage ofessential amino acids than wild-type.

U.S. Pat. No. 5,633,436 discloses plants comprising a higher content ofsulfur-containing amino acids; U.S. Pat. No. 5,885,801 discloses plantscomprising a high threonine content; U.S. Pat. No. 5,885,802 disclosesplants comprising a high methionine content; U.S. Pat. No. 5,912,414discloses plants comprising a high methionine content; U.S. Pat. No.5,990,389 discloses plants comprising a high lysine content; U.S. Pat.No. 6,459,019 discloses plants comprising an increased lysine andthreonine content; International Patent Appl. Pub. No. WO 98/42831discloses plants comprising a high lysine content; International PatentAppl. Pub. No. WO 96/01905 discloses plants comprising a high threoninecontent; and International Patent Appl. Pub. No. WO 95/15392 disclosesplants comprising a high lysine content.

N. Definitions

In the description and tables herein, a number of terms are used. Inorder to provide a clear and consistent understanding of thespecification and claims, the following definitions are provided:

Allele: Any of one or more alternative forms of a gene locus, all ofwhich alleles relate to one trait or characteristic. In a diploid cellor organism, the two alleles of a given gene occupy corresponding locion a pair of homologous chromosomes.

Backcrossing: A process in which a breeder repeatedly crosses hybridprogeny, for example a first generation hybrid (F₁), back to one of theparents of the hybrid progeny. Backcrossing can be used to introduce oneor more single locus conversions from one genetic background intoanother.

Barren Plants: Plants that are barren, i.e., lack an ear with grain orhave an ear with only a few scattered kernels.

Cg: Colletotrichum graminicola rating. Rating times 10 is approximatelyequal to percent total plant infection.

CLN: Corn Lethal Necrosis (combination of Maize chlorotic mottle virusand Maize dwarf mosaic virus) rating. Numerical ratings are based on aseverity scale where 1=most resistant to 9=susceptible.

Cn: Corynebacterium nebraskense rating. Rating times 10 is approximatelyequal to percent total plant infection.

Crossing: The mating of two parent plants.

Cross-pollination: Fertilization by the union of two gametes fromdifferent plants.

Cz: Cercospora zeae-maydis rating. Rating times 10 is approximatelyequal to percent total plant infection.

Dgg: Diatraea grandiosella girdling rating (values are percent plantsgirdled and stalk lodged).

Diploid: A cell or organism having two sets of chromosomes.

Dropped Ears: Ears that have fallen from the plant to the ground.

Dsp: Diabrotica species root ratings (1=least affected to 9=severepruning).

Ear-Attitude: The attitude or position of the ear at harvest scored asupright, horizontal, or pendant.

Ear-Cob Color: The color of the cob, scored as white, pink, red, orbrown.

Ear-Cob Diameter: The average diameter of the cob measured at themidpoint.

Ear-Cob Strength: A measure of mechanical strength of the cobs tobreakage, scored as strong or weak.

Ear-Diameter: The average diameter of the ear at its midpoint.

Ear-Dry Husk Color: The color of the husks at harvest scored as buff,red, or purple.

Ear-Fresh Husk Color: The color of the husks 1 to 2 weeks afterpollination scored as green, red, or purple.

Ear-Husk Bract: The length of an average husk leaf scored as short,medium, or long.

Ear-Husk Cover: The average distance from the tip of the ear to the tipof the husks, minimum value no less than zero.

Ear-Husk Opening: An evaluation of husk tightness at harvest scored astight, intermediate, or open.

Ear-Length: The average length of the ear.

Ear-Number Per Stalk: The average number of ears per plant.

Ear-Shank Internodes: The average number of internodes on the ear shank.

Ear-Shank Length: The average length of the ear shank.

Ear-Shelling Percent: The average of the shelled grain weight divided bythe sum of the shelled grain weight and cob weight for a single ear.

Ear-Silk Color: The color of the silk observed 2 to 3 days after silkemergence scored as green-yellow, yellow, pink, red, or purple.

Ear-Taper (Shape): The taper or shape of the ear scored as conical,semi-conical, or cylindrical.

Ear-Weight: The average weight of an ear.

Early Stand: The percent of plants that emerge from the ground asdetermined in the early spring.

Emasculate: The removal of plant male sex organs or the inactivation ofthe organs with a cytoplasmic or nuclear genetic factor or a chemicalagent conferring male sterility.

Enzymes: Molecules which can act as catalysts in biological reactions.

ER: Ear rot rating (values approximate percent ear rotted).

F₁ Hybrid: The first generation progeny of the cross of two nonisogenicplants.

Final Stand Count: The number of plants just prior to harvest.

GDUs: Growing degree units which are calculated by the Barger Method,where the heat units for a 24-h period are calculated as GDUs=[(Maximumdaily temperature+Minimum daily temperature)/2]−50. The highest maximumdaily temperature used is 86° F. and the lowest minimum temperature usedis 50° F.

GDUs to Shed: The number of growing degree units (GDUs) or heat unitsrequired for a variety to have approximately 50% of the plants sheddingpollen as measured from time of planting. GDUs to shed is determined bysumming the individual GDU daily values from planting date to the dateof 50% pollen shed.

GDUs to Silk: The number of growing degree units for a variety to haveapproximately 50% of the plants with silk emergence as measured fromtime of planting. GDUs to silk is determined by summing the individualGDU daily values from planting date to the date of 50% silking.

Genetic Complement: An aggregate of nucleotide sequences, the expressionof which sequences defines the phenotype in corn plants, or componentsof plants including cells or tissue.

Genotype: The genetic constitution of a cell or organism.

Haploid: A cell or organism having one set of the two sets ofchromosomes in a diploid.

Hc2: Helminthosporium carbonum race 2 rating. Rating times 10 isapproximately equal to percent total plant infection.

Hc3: Helminthosporium carbonum race 3 rating. Rating times 10 isapproximately equal to percent total plant infection.

Hm: Helminthosporium maydis race 0 rating. Rating times 10 isapproximately equal to percent total plant infection.

Ht1: Helminthosporium turcicum race 1 rating. Rating times 10 isapproximately equal to percent total plant infection.

Ht2: Helminthosporium turcicum race 2 rating. Rating times 10 isapproximately equal to percent total plant infection.

HtG: Chlorotic-lesion type resistance. “+” indicates the presence of Htchlorotic-lesion type resistance; “−” indicates absence of Htchlorotic-lesion type resistance; and “+/−” indicates segregation of Htchlorotic-lesion type resistance. Rating times 10 is approximately equalto percent total plant infection.

Kernel-Aleurone Color: The color of the aleurone scored as white, pink,tan, brown, bronze, red, purple, pale purple, colorless, or variegated.

Kernel-Cap Color: The color of the kernel cap observed at dry stage,scored as white, lemon-yellow, yellow, or orange.

Kernel-Endosperm Color: The color of the endosperm scored as white, paleyellow, or yellow.

Kernel-Endosperm Type: The type of endosperm scored as normal, waxy, oropaque.

Kernel-Grade: The percent of kernels that are classified as rounds.

Kernel-Length: The average distance from the cap of the kernel to thepedicel.

Kernel-Number Per Row: The average number of kernels in a single row.

Kernel-Pericarp Color: The color of the pericarp scored as colorless,red-white crown, tan, bronze, brown, light red, cherry red, orvariegated.

Kernel-Row Direction: The direction of the kernel rows on the ear scoredas straight, slightly curved, spiral, or indistinct (scattered).

Kernel-Row Number: The average number of rows of kernels on a singleear.

Kernel-Side Color: The color of the kernel side observed at the drystage, scored as white, pale yellow, yellow, orange, red, or brown.

Kernel-Thickness: The distance across the narrow side of the kernel.

Kernel-Type: The type of kernel scored as dent, flint, or intermediate.

Kernel-Weight: The average weight of a predetermined number of kernels.

Kernel-Width: The distance across the flat side of the kernel.

Kz: Kabatiella zeae rating. Rating times 10 is approximately equal topercent total plant infection.

Leaf-Angle: Angle of the upper leaves to the stalk scored as upright (0to 30 degrees), intermediate (30 to 60 degrees), or lax (60 to 90degrees).

Leaf-Color: The color of the leaves 1 to 2 weeks after pollinationscored as light green, medium green, dark green, or very dark green.

Leaf-Length: The average length of the primary ear leaf.

Leaf-Longitudinal Creases: A rating of the number of longitudinalcreases on the leaf surface 1 to 2 weeks after pollination. Creases arescored as absent, few, or many.

Leaf-Marginal Waves: A rating of the waviness of the leaf margin 1 to 2weeks after pollination, rated as none, few, or many.

Leaf-Number: The average number of leaves of a mature plant. Countingbegins with the cotyledonary leaf and ends with the flag leaf.

Leaf-Sheath Anthocyanin: A rating of the level of anthocyanin in theleaf sheath 1 to 2 weeks after pollination, scored as absent,basal-weak, basal-strong, weak, or strong.

Leaf-Sheath Pubescence: A rating of the pubescence of the leaf sheath.Ratings are taken 1 to 2 weeks after pollination and scored as light,medium, or heavy.

Leaf-Width: The average width of the primary ear leaf measured at itswidest point.

Linkage: A phenomenon wherein alleles on the same chromosome tend tosegregate together more often than expected by chance if theirtransmission was independent.

LSS: Late season standability (values times 10 approximate percentplants lodged in disease evaluation plots).

Marker: A readily detectable phenotype, preferably inherited incodominant fashion (both alleles at a locus in a diploid heterozygoteare readily detectable), with no environmental variance component, i.e.,heritability of 1.

Moisture: The moisture of the grain at harvest.

On1: Ostrinia nubilalis 1st brood rating (1=resistant to 9=susceptible).

On2: Ostrinia nubilalis 2nd brood rating (1=resistant to 9=susceptible).

Phenotype: The detectable characteristics of a cell or organism, whichcharacteristics are the manifestation of gene expression.

Quantitative Trait Loci (QTL): Quantitative trait loci (QTL) refer togenetic loci that control to some degree numerically representabletraits that are usually continuously distributed.

Regeneration: The development of a plant from tissue culture.

Relative Maturity: A maturity rating based on regression analysis. Theregression analysis is developed by utilizing check hybrids and theirpreviously established day rating versus actual harvest moistures.Harvest moisture on the hybrid in question is determined and thatmoisture value is inserted into the regression equation to yield arelative maturity.

Resistance: As used herein, the terms “resistance” and “tolerance” areused interchangeably to describe plants that show no symptoms to aspecified biotic pest, pathogen, abiotic influence or environmentalcondition. These terms are also used to describe plants showing somesymptoms but that are still able to produce marketable product with anacceptable yield. Some plants that are referred to as resistant ortolerant are only so in the sense that they may still produce a crop,even though the plants are stunted and the yield is reduced.

Root Lodging: Root lodging is the percentage of plants that root lodge.A plant is counted as root lodged if a portion of the plant leans fromthe vertical axis by approximately 30 degrees or more.

Royal Horticultural Society (RHS) Colour Chart Value: The RHS ColourChart is a standardized reference which allows accurate identificationof any color. A color's designation on the chart describes its hue,brightness, and saturation. A color is precisely named by the RHS ColourChart by identifying the group name, sheet number, and letter, e.g.,Yellow-Orange Group 19A or Red Group 41B.

Seedling Color: Color of leaves at the 6 to 8 leaf stage.

Seedling Height: Plant height at the 6 to 8 leaf stage.

Seedling Vigor: A visual rating of the amount of vegetative growth on a1 to 9 scale, where 1 equals best. The score is taken when the averageentry in a trial is at the fifth leaf stage.

Selection Index: The selection index gives a single measure of hybrid'sworth based on information from multiple traits. One of the traits thatis almost always included is yield. Traits may be weighted according tothe level of importance assigned to them.

Self-Pollination: The transfer of pollen from the anther to the stigmaof the same plant.

Single Locus Converted (Conversion) Plant: Plants which are developed bya plant breeding technique called backcrossing, wherein essentially allof the morphological and physiological characteristics of a corn varietyare recovered in addition to the characteristics of the single locustransferred into the variety via the backcrossing technique and/or bygenetic transformation.

Sr: Sphacelotheca reiliana rating is actual percent infection.

Stalk-Anthocyanin: A rating of the amount of anthocyanin pigmentation inthe stalk. The stalk is rated 1 to 2 weeks after pollination as absent,basal-weak, basal-strong, weak, or strong.

Stalk-Brace Root Color: The color of the brace roots observed 1 to 2weeks after pollination as green, red, or purple.

Stalk-Diameter: The average diameter of the lowest visible internode ofthe stalk.

Stalk-Ear Height: The average height of the ear measured from the groundto the point of attachment of the ear shank of the top developed ear tothe stalk.

Stalk-Internode Direction: The direction of the stalk internode observedafter pollination as straight or zigzag.

Stalk-Internode Length: The average length of the internode above theprimary ear.

Stalk Lodging: The percentage of plants that did stalk lodge. Plants arecounted as stalk lodged if the plant is broken over or off below theear.

Stalk-Nodes With Brace Roots: The average number of nodes having braceroots per plant.

Stalk-Plant Height: The average height of the plant as measured from thesoil to the tip of the tassel.

Stalk-Tillers: The percent of plants that have tillers. A tiller isdefined as a secondary shoot that has developed as a tassel capable ofshedding pollen.

Staygreen: Staygreen is a measure of general plant health near the timeof black layer formation (physiological maturity). It is usuallyrecorded at the time the ear husks of most entries within a trial haveturned a mature color. Scoring is on a 1 to 9 basis where 1 equals best.

STR: Stalk rot rating (values represent severity rating of 1=25% ofinoculated internode rotted to 9=entire stalk rotted and collapsed).

Substantially Equivalent: A characteristic that, when compared, does notshow a statistically significant difference (e.g., p=0.05) from themean.

SVC: Southeastern Virus Complex (combination of Maize chlorotic dwarfvirus and Maize dwarf mosaic virus) rating; numerical ratings are basedon a severity scale where 1=most resistant to 9=susceptible.

Tassel-Anther Color: The color of the anthers at 50% pollen shed scoredas green-yellow, yellow, pink, red, or purple.

Tassel-Attitude: The attitude of the tassel after pollination scored asopen or compact.

Tassel-Branch Angle: The angle of an average tassel branch to the mainstem of the tassel scored as upright (less than 30 degrees),intermediate (30 to 45 degrees), or lax (greater than 45 degrees).

Tassel-Branch Number: The average number of primary tassel branches.

Tassel-Glume Band: The closed anthocyanin band at the base of the glumescored as present or absent.

Tassel-Glume Color: The color of the glumes at 50% shed scored as green,red, or purple.

Tassel-Length: The length of the tassel measured from the base of thebottom tassel branch to the tassel tip.

Tassel-Peduncle Length: The average length of the tassel peduncle,measured from the base of the flag leaf to the base of the bottom tasselbranch.

Tassel-Pollen Shed: A visual rating of pollen shed determined by tappingthe tassel and observing the pollen flow of approximately five plantsper entry. Rated on a 1 to 9 scale where 9=sterile, 1=most pollen.

Tassel-Spike Length: The length of the spike measured from the base ofthe top tassel branch to the tassel tip.

Test Weight: Weight of the grain in pounds for a given volume (bushel)adjusted to 15.5% moisture.

Tissue Culture: A composition comprising isolated cells of the same or adifferent type or a collection of such cells organized into parts of aplant.

Transgene: A genetic locus comprising a sequence which has beenintroduced into the genome of a corn plant by transformation orsite-specific recombination.

Yield: Yield of grain at harvest adjusted to 15.5% moisture.

O. Deposit Information

A deposit of corn hybrid SVSK6143 and inbred parent linesSHY-6S15-9078LP and SHY-6RHBE322, disclosed above and recited in theclaims, has been made with the American Type Culture Collection (ATCC),10801 University Blvd., Manassas, Va. 20110-2209. The dates of depositfor hybrid SVSK6143 and inbred parent lines SHY-6S15-9078LP andSHY-6RHBE322 were Apr. 21, 2017, May 22, 2017, and May 22, 2017,respectively. The accession numbers for those deposited seeds of cornhybrid SVSK6143 and inbred parent lines SHY-6S15-9078LP and SHY-6RHBE322are ATCC Accession No. PTA-124111, ATCC Accession No. PTA-124211, andATCC Accession No. PTA-124212, respectively. Upon issuance of a patent,all restrictions upon the deposits will be removed, and the deposits areintended to meet all of the requirements of 37 C.F.R. § 1.801-1.809. Thedeposits will be maintained in the depository for a period of 30 years,or 5 years after the last request, or for the effective life of thepatent, whichever is longer, and will be replaced if necessary duringthat period.

Although the foregoing invention has been described in some detail byway of illustration and example for purposes of clarity andunderstanding, it will be obvious that certain changes and modificationsmay be practiced within the scope of the invention, as limited only bythe scope of the appended claims.

All references cited herein are hereby expressly incorporated herein byreference.

What is claimed:
 1. A corn plant comprising at least a first set of thechromosomes of corn line SHY-6S15-9078LP or corn line SHY-6RHBE322, asample of seed of said lines having been deposited under ATCC AccessionNumber PTA-124211 and ATCC Accession Number PTA-124212, respectively. 2.A corn seed that produces the plant of claim
 1. 3. The plant of claim 1,wherein the plant is a plant of corn hybrid SVSK6143, a sample of seedof said hybrid having been deposited under ATCC Accession NumberPTA-124111.
 4. The seed of claim 2, wherein the seed is a seed of cornhybrid SVSK6143, a sample of seed of said hybrid having been depositedunder ATCC Accession Number PTA-124111.
 5. The seed of claim 2, whereinthe seed is a seed of corn line SHY-6S15-9078LP or corn lineSHY-6RHBE322.
 6. A plant part of the plant of claim 1, wherein the plantpart comprises a cell of said plant.
 7. A corn plant having all thephysiological and morphological characteristics of the corn plant ofclaim
 1. 8. A tissue culture of regenerable cells of the plant ofclaim
 1. 9. A method of vegetatively propagating the corn plant of claim1, the method comprising the steps of: (a) collecting tissue capable ofbeing propagated from the plant according to claim 1; and (b)propagating a corn plant from said tissue, wherein said propagated cornplant comprises all of the morphological and physiologicalcharacteristics of the corn plant of claim
 1. 10. A method ofintroducing a trait into a corn line, the method comprising: (a)utilizing as a recurrent parent a plant of corn line SHY-6S15-9078LP orcorn line SHY-6RHBE322, by crossing a plant of corn line SHY-6S15-9078LPor corn line SHY-6RHBE322 with a donor corn plant that comprises a traitto produce F progeny, a sample of seed of said lines having beendeposited under ATCC Accession Number PTA-124211 and ATCC AccessionNumber PTA-124212, respectively; (b) selecting an F₁ progeny thatcomprises the trait; (c) backcrossing the selected F₁ progeny with aplant of the same corn line used as the recurrent parent in step (a) toproduce backcross progeny; (d) selecting a backcross progeny comprisingthe trait and the morphological and physiological characteristics of therecurrent parent corn line used in step (a); and (e) repeating steps (c)and (d) three or more times to produce a selected fourth or higherbackcross progeny.
 11. A corn plant produced by the method of claim 10,wherein said plant comprises said introduced trait and otherwisecomprises all of the morphological and physiological characteristics ofthe plant obtained from said deposited seed when grown under the sameenvironmental conditions.
 12. A method of producing a corn plantcomprising an added trait, the method comprising introducing a transgeneconferring the trait into a plant of corn hybrid SVSK6143, corn lineSHY-6S15-9078LP, or corn line SHY-6RHBE322, a sample of seed of saidhybrid and lines having been deposited under ATCC Accession NumberPTA-124111, ATCC Accession Number PTA-124211, and ATCC Accession NumberPTA-124212, respectively.
 13. A corn plant produced by the method ofclaim 12, wherein said plant comprises said added trait and otherwisecomprises all of the morphological and physiological characteristics ofthe plant obtained from said deposited seed when grown under the sameenvironmental conditions.
 14. A corn plant comprising at least a firstset of the chromosomes of corn line SHY-6S15-9078LP or corn lineSHY-6RHBE322, a sample of seed of said lines having been deposited underATCC Accession Number PTA-124211 and ATCC Accession Number PTA-124212,further comprising a transgene.
 15. The plant of claim 14, wherein thetransgene confers a trait selected from the group consisting of malesterility, herbicide tolerance, insect resistance, pest resistance,disease resistance, modified fatty acid metabolism, environmental stresstolerance, modified carbohydrate metabolism, and modified proteinmetabolism.
 16. A corn plant comprising at least a first set of thechromosomes of corn line SHY-6S15-9078LP or corn line SHY-6RHBE322, asample of seed of said lines having been deposited under ATCC AccessionNumber PTA-124211 and ATCC Accession Number PTA-124212, furthercomprising a single locus conversion and otherwise comprising all of themorphological and physiological characteristics of the plant obtainedfrom said deposited seed when grown under the same environmentalconditions.
 17. The plant of claim 16, wherein the single locusconversion confers a trait selected from the group consisting of malesterility, herbicide tolerance, insect resistance, pest resistance,disease resistance, modified fatty acid metabolism, environmental stresstolerance, modified carbohydrate metabolism, and modified proteinmetabolism.
 18. A method for producing a seed of a corn plant derivedfrom at least one of corn hybrid SVSK6143, corn line SHY-6S15-9078LP, orcorn line SHY-6RHBE322, the method comprising the steps of: (a) crossinga corn plant according to claim 1 with itself or a second corn plant;and (b) allowing seed of a hybrid SVSK6143, line SHY-6S15-9078LP, orline SHY-6RHBE322-derived corn plant to form.
 19. A method of producinga seed of a hybrid SVSK6143, line SHY-6S15-9078LP, or lineSHY-6RHBE322-derived corn plant, the method comprising the steps of: (a)producing a hybrid SVSK6143, line SHY-6S15-9078LP, or lineSHY-6RHBE322-derived corn plant from a seed produced by crossing a cornplant according to claim 1 with itself or a second corn plant; and (b)crossing the hybrid SVSK6143, line SHY-6S15-9078LP, or lineSHY-6RHBE322-derived corn plant with itself or a different corn plant toobtain a seed of a further hybrid SVSK6143, line SHY-6S15-9078LP, orline SHY-6RHBE322-derived corn plant.
 20. The method of claim 19, themethod further comprising repeating said producing and crossing steps of(a) and (b) using a seed from said step (b) for producing a plantaccording to step (a) for at least one generation to produce a seed ofan additional hybrid SVSK6143, line SHY-6S15-9078LP, or lineSHY-6RHBE322-derived corn plant.
 21. A method of producing an ear ofcorn, the method comprising: (a) obtaining the plant according to claim1, wherein the plant has been cultivated to maturity; and (b) collectingan ear of corn from the plant.
 22. The plant of claim 1, wherein theplant is a plant of said corn line SHY-6S15-9078LP or corn lineSHY-6RHBE322.